Reference:
  Author: Darty, Kévin and Denise, Alain and Ponty, Yann 
  Title: "VARNA: Interactive drawing and editing of the RNA secondary structure"
  Journal: Bioinformatics
  Year: 2009
  Volume: 25
  Number: 15
  Pages: 1974-1975
  DOI: http://dx.doi.org/10.1093/bioinformatics/btp250
  URL: http://bioinformatics.oxfordjournals.org/content/25/15/1974
  eprint: http://bioinformatics.oxfordjournals.org/content/25/15/1974.full.pdf+html 
